Micropore induced shock wave sacculus pipe and systemTechnical Field
The application belongs to the field of minimally invasive interventional therapy, and particularly relates to a micropore induced shock wave sacculus catheter and system applied to calcified lesion vascular therapy.
Background
With the aging of the population and the improvement of the living standard, the incidence of vascular diseases increases year by year. The progression of the vascular condition causes plaque in the vessel wall to evolve into calcium deposits, thereby narrowing the artery and restricting blood flow. When calcification of blood vessels occurs, the current major conventional practice is to use balloons for dilation, stent implantation or rotational atherectomy balloons to exfoliate plaque. However, these treatments have significant drawbacks, often associated with vascular injury and complications. Such as balloon dilatation and stent implantation, can produce tearing of the intima of the vessel, which often results in hyperplasia of the endothelium of the vessel, creating a risk of restenosis.
To solve this problem, the company of shock wave medicine (SHOCKWAVE MEDICAL) in the United states has proposed the use of the hydroelectrical effect lithotripsy technique in angioplasty (patent application number: 201880040835.6). The basic principle of the method is that a certain electric field is applied to liquid, the liquid generates cavitation under the action of the electric field, bubbles generated by cavitation collapse instantly to generate shock waves, and therefore the purpose of breaking calcified pathological tissues is achieved on the premise that vascular intima is not damaged. However, this method has a problem that an electric field is directly applied to the inside of the liquid, and the electric field intensity required for generating a shock wave of sufficient intensity is high and the current output is large. In case the damaged weeping condition of sacculus appears, the high voltage heavy current passes through the human body, can cause serious human electric shock accident, endangers patient and medical personnel life safety even. In addition, the high voltage and high current output also causes excessive electrothermal conversion and energy release, which imposes more severe requirements on the design of the catheter. Therefore, it is desirable to design a balloon catheter system capable of generating a shock wave by using a low-voltage and low-current energy source to improve product safety.
Disclosure of Invention
The utility model provides an overcome current technical defect, design a micropore induction shock wave sacculus pipe and system, this micropore induction shock wave sacculus pipe and system reduce substantially through setting up effectual micropore induction shock wave generating device and realize the required electric field intensity threshold value of liquid cavitation, and then realize producing strong shock wave under the low-voltage weak current condition, reduce substantially the risk of product in the use.
One purpose of this application is realized through following technical scheme:
a micropore induced shock wave balloon catheter comprises an axially extending slender member, a working bag body arranged at the far end part of the slender member, a conducting wire and a liquid injection pipe, wherein the conducting wire and the liquid injection pipe are arranged in a cavity of the slender member, the working bag body is communicated with the liquid injection pipe in a fluid mode, an electric field generating mechanism is arranged in the working bag body, a micropore induced shock wave generating device is arranged to wrap the electric field generating mechanism, the electric field generating mechanism is electrically connected with external equipment through the conducting wire, a micropore mechanism is arranged on the micropore induced shock wave generating device, the micropore mechanism penetrates through the wall of the micropore induced shock wave generating device, the micropore mechanism can prevent liquid from entering by utilizing the surface tension of the micropore induced shock wave generating device, and the micropore induced shock wave generating device can isolate the electric field generating mechanism from liquid flowing into the working bag body.
The above object of the present application can also be achieved by the following technical solutions:
in one embodiment, the surface properties and dimensional structure of the microporous means conform to the following quantitative relationship:
wherein P is the absolute pressure of the liquid in the working capsule, delta is the surface tension coefficient, D is the equivalent hydraulic diameter of the pores, and beta is the contact angle of the liquid on the wall surface of the micropores. In the calculation process, for a round micropore, D is the diameter of the micropore, and for a micropore structure with a non-round shape such as a square shape, a triangular shape and the like or other shapes, D is the equivalent hydraulic diameter of the micropore structure.
In a preferred embodiment, the microporous means consists of a plurality of micropores.
In a preferred embodiment, the microporous mechanism is an array structure composed of a plurality of micropores arranged orderly or disorderly.
In a preferred embodiment, the microporous structure is a honeycomb-like array structure composed of a plurality of micropores.
In a preferred embodiment, the micropores of the microporous means are capable of blocking the passage of liquid and allowing the passage of gas.
In a preferred embodiment, the microporous structure is hydrophobic.
In a preferred embodiment, the surface of the micropores in the microporous structure is coated with a hydrophobic coating, or the microporous structure has a hydrophobic microporous structure, or the microporous structure is made of a hydrophobic material, or the microporous structure is a combination thereof.
In a preferred embodiment, the microporous structure has a pore structure of the order of millimeters, micrometers or nanometers.
In a preferred embodiment, the micro-porous induced shock wave generating means is an electrically insulating member.
In one embodiment, a fluid return tube is disposed within the lumen of the elongate member, the fluid return tube being in fluid communication with the working balloon and the infusion tube, respectively.
In a preferred embodiment, the distal outlet of the return tube is disposed at the distal end of the working balloon, and the distal outlet of the injection tube is disposed at the proximal end of the working balloon.
In a preferred embodiment, the distal outlet of the liquid return tube is disposed at the proximal end of the working balloon, and the distal outlet of the liquid injection tube is disposed at the distal end of the working balloon.
In one embodiment, the elongate member includes a guide wire lumen having a proximal outlet disposed on the catheter handle and a distal outlet disposed at the distal end of the shockwave balloon catheter, the guide wire lumen being fluidly isolated from other components of the shockwave balloon catheter.
In a preferred embodiment, the elongate member includes an outer sheath, the proximal end of the working balloon being sealingly connected to the distal end of the outer sheath, and the distal end of the working balloon being sealingly connected to the distal portion of the guidewire lumen.
In one embodiment, a protective balloon is provided outside the working balloon, connected to the elongate member and surrounding the working balloon.
In one embodiment, the electric field generating mechanism comprises an electrode pair consisting of a positive electrode and a negative electrode, and the positive electrode and the negative electrode are respectively electrically connected with the external device through leads.
In a preferred embodiment, the electric field generating mechanism includes a plurality of electrode pairs, and the electrode pairs are connected in parallel by a connecting wire and electrically connected to the external device through the connecting wire.
In a preferred embodiment, the connecting line is of one-piece design with the line.
The other purpose of the application is realized by the following technical scheme:
a micropore induced shock wave sacculus conduit system comprises an electric field generating device and the micropore induced shock wave sacculus conduit, wherein the electric field generating device comprises a man-machine interaction module, a control module, a power module and a high-voltage pulse output module, the man-machine interaction module is electrically connected with the control module, the control module is respectively electrically connected with the power module and the high-voltage pulse output module, the high-voltage pulse output module is electrically connected with the micropore induced shock wave sacculus conduit, the micropore induced shock wave sacculus conduit comprises an axially extending slender component, a working bag body arranged at the distal end part of the slender component, a lead and a liquid injection pipe arranged in the cavity of the slender component, an electric field generating mechanism arranged in the working bag body and a micropore induced shock wave generating device wrapping the electric field generating mechanism, the working bag body is in fluid communication with the liquid injection pipe, the electric field generating mechanism is electrically connected with the high-voltage pulse output module through the lead, a micropore mechanism is arranged on the micropore induced shock wave generating device, the micropore mechanism penetrates through the wall of the micropore induced shock wave generating device, and the micropore mechanism can prevent liquid from entering the micropore induced shock wave generating device by utilizing the surface tension of the micropore mechanism, so that the micropore induced shock wave generating liquid can be isolated from the micropore mechanism.
The above object of the present application can also be achieved by the following technical solutions:
in one embodiment, the electric field generating mechanism includes an electrode pair consisting of a positive electrode and a negative electrode, and the positive electrode and the negative electrode are electrically connected to the high-voltage pulse output module through the wires, respectively.
In a preferred embodiment, the electric field generating mechanism includes a plurality of electrode pairs, and the plurality of electrode pairs are connected in parallel by a connecting wire and electrically connected to the high voltage pulse output module by the wire.
Compare with prior art, the advantage of this application lies in:
in the shock wave balloon catheter in the prior art, electrodes are exposed outside and are directly contacted with liquid in a working balloon body, namely, an electric field is directly applied to the liquid to generate a liquid-electric effect. The electric field strength required to generate the electrohydraulic effect is high, and generally, a high voltage of about 3000V is required. The high voltage causes the fluid between the electrode pair to be completely broken down and discharged, the discharge resistance is small, and the current is large (generally more than 20A). Once the condition of sacculus damage weeping appears, high voltage heavy current passes through the human body, can cause serious human electric shock accident, endangers patient and medical personnel life safety even. Different from the situation that the micropore induced shock wave generating device is arranged in the shock wave generating unit, the micropore mechanism arranged on the micropore induced shock wave generating device automatically prevents liquid in the working bag body from contacting the electric field generating mechanism by utilizing the surface tension of the liquid, the electric field generating mechanism only punctures a micro liquid bridge in the micropore, the puncture voltage is obviously reduced, and the lowest voltage can reach 500V. In addition, the micro liquid bridge is not in contact with the electrodes in the electric field generating structure, and air which is not punctured exists between the electrodes, so that the generating resistance is obviously increased, and the current is greatly reduced (generally 0.1-0.2A). Therefore, by arranging the micropore induced shock wave generating device, a threshold value (an electric field intensity threshold value required for realizing liquid cavitation) for generating the liquid electric effect cavitation can be obviously reduced, so that the discharge voltage and the discharge current are greatly reduced, and then, the strong shock wave is generated under the condition of low voltage and weak current, the system safety is obviously improved, and the risk of the system in the using process is reduced.
Drawings
Fig. 1 is a schematic diagram of the overall structure of the micropore-induced shockwave balloon catheter of the present application.
FIG. 2 is a schematic view of the force analysis of a liquid in a single well of the present micro-well device.
FIG. 3 is a schematic diagram of the induction of the electrooptic effect in the micropores.
FIG. 4 is a graph of the distribution of the internal resistance of the micropore induced shock wave generator.
FIG. 5 is a schematic structural diagram of one embodiment of a micropore mechanism according to the present application
Fig. 6 is a schematic structural view of a distal portion of a shockwave balloon catheter of the present application.
Fig. 7 is a schematic diagram of the overall configuration of the micropore-induced shockwave balloon catheter system of the present application.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is further described in detail below by referring to the accompanying drawings and examples.
Example one
As shown in fig. 1, a micropore inducedshockwave balloon catheter 2 comprises an axially extendingelongated member 21, a workingballoon 22 disposed at a distal end portion of theelongated member 21, acatheter handle 24 disposed at a proximal end of theelongated member 21, alead wire 26 and aliquid injection tube 27 disposed in a lumen of theelongated member 21, an electric field generating means 23 disposed in the workingballoon 22, and a micropore induced shockwave generating means 25 disposed to surround the electric field generating means 23, the workingballoon 22 being in fluid communication with theliquid injection tube 27, the electric field generating means 23 being electrically connected to an external device through thelead wire 26, the micropore induced shockwave generating means 25 being an electrically insulating member, a micropore means 251 being provided on the micropore induced shockwave generating means 25, the micropore means 251 penetrating through a wall of the micropore induced shockwave generating means, the micropore means 251 being capable of blocking liquid from entering by its own surface tension, so that the micropore induced shockwave generating means 25 is capable of isolating the electric field generating means 23 from liquid flowing into the workingballoon 22.
In order to effectively prevent the liquid inside the workingcapsule 22 from entering the micropore-induced shock wave generating device 51 through themicropore mechanism 251 to form a flooding discharge deterioration phenomenon, the surface properties and the dimensional structure of themicropores 2511 in themicropore mechanism 251 conform to the following quantitative relationship:
in the above formula, P is the absolute pressure of the liquid in the working capsule, delta is the surface tension coefficient, D is the pore equivalent hydraulic diameter, and beta is the contact angle of the liquid on the wall surface of the micropore. In the calculation process, for a round micropore, D is the diameter of the micropore, and for a micropore structure with a non-round shape such as a square shape, a triangular shape and the like or other shapes, D is the equivalent hydraulic diameter of the micropore structure.
As shown in FIG. 2, where LD represents liquid, GS represents gas, and WB represents the wall of the micro-well, the theoretical derivation process is as follows:
surface tension F of liquidδ =ρπD (2)
The component of the surface tension in the y direction is:
Fy =Fδ cosα=Fδ cos(π-β)=-δπDcosβ (3)
assuming that the absolute pressure of the Liquid (LD) in the capsule is P, the force applied by the liquid pressure at the inlet of the micro-hole in the axial direction of the micro-hole can be expressed as:
when the liquid pressure in the working capsule body is generated at the inlet of the micropore, the stress along the axial direction of the micropore is smaller than the component of the surface tension in the y direction, namely Ff <Fy In the process, the liquid can not overcome the surface tension effect and passes through themicropores 2511, so that the liquid can be effectively intercepted, and the integrated electric field generating mechanism is isolated from the liquid flowing into the working capsule body through the micropores.
Formula 3-4 is substituted into available:
the above formula can also be expressed as
Therefore, as long as the inner diameter D and surface tension coefficient δ of themicropores 251 and the contact angle β with the liquid in the working capsule conform to the above formula, the liquid will be effectively intercepted and will not pass through the micropores.
The above equation holds true for non-circular or other irregular pore structures such as squares, triangles, etc., where D inequation 1 is the equivalent hydraulic diameter of the pore structure.
The conditions under which the electrohydraulic effect occurs are mainly influenced by two factors: a threshold free energy for cavitation and an electric field strength required for cavitation core formation. The existing shock wave balloon catheter directly applies an electric field to liquid to generate a liquid-electricity effect, and the free energy threshold required by cavitation generation in macroscopic bulk liquid is high. In addition, the electric field inside the bulk liquid is uniformly distributed, and the electric field intensity required for generating the liquid-electric effect is high, and generally about 3000V high voltage is required. In addition, the high voltage completely discharges the fluid between the pair of electrodes, and the discharge resistance is small and the current is large (generally 20A or more). Interfacial hydrodynamics shows that the liquid in the micropores can form micro liquid bridges under the action of surface tension, the micro liquid bridges have a scale effect, and the threshold value of the liquid-electricity effect vacuole generation is obviously lower than that of the large-space macroscopic fluid in the pool. Based on the principle, the micropore induced shockwave generating device 25 is arranged between the workingcapsule body 22 and the electricfield generating mechanism 23, the micropore induced shock wave generating device is hermetically wrapped on the electricfield generating mechanism 23, amicropore mechanism 251 is arranged on the micropore induced shockwave generating device 25, themicropore mechanism 251 can allow gas to pass through but not water to pass through, water forms a microscale liquid bridge in a micropore, the electric field generated by the electricfield generating mechanism 23 only needs to puncture the microfluidic bridge in the micropore, and the puncture voltage is remarkably reduced.
As shown in fig. 3, the micro-pore mechanism can utilize the surface tension of the liquid to automatically intercept the liquid in the working capsule to enter the electric field generating mechanism. A meniscus liquid arc A is formed in a micropore in the micropore mechanism at an outlet far away from an electrode, an electric field E is applied to the meniscus liquid arc A, due to an interface effect, the free energy threshold generated by liquid cavitation at a gas-liquid interface and a solid-liquid interface is greatly reduced, and the free energy required by cavitation is obviously reduced compared with bulk phase liquid. In addition, the internal electric field distribution of the meniscus arc A is odd due to the scale effect, the electric field distribution is uneven, and a cavitation core is formed in an area with high local electric field intensity of an interface at the earliest so as to induce cavitation. Therefore, the micropore mechanism can promote the generation of cavitation bubbles and reduce the voltage required by the formation of cavitation cores, and the minimum voltage can reach 500V.
As shown in fig. 3, since the Liquid (LD) in the working capsule is not in direct contact with the electric field generating mechanism, air (GS) which is not broken down exists between the liquid bridge and the electrode in the electricfield generating mechanism 23, and electric fields are uniformly distributed in the air (GS) and the Liquid (LD), as the electric field intensity applied to the air does not reach the breakdown critical point of the air, and the electric field applied to the meniscus arc a reaches the liquid breakdown electric field intensity critical point, a breakdown arc can be generated in the liquid arc. In the discharging process, the electrode discharging needs to pass through the non-punctured insulating air, electrons need to be conducted through the air layer and the meniscus arc A, and the conduction resistance is obviously increased. As shown in fig. 4, since the resistance R2 of the meniscus arc a is relatively small, the process resistance is mainly due to the resistances R1 and R3 of the air layers on both sides of the micro-hole, and thus the current is greatly reduced (generally 0.1A to 0.2A). Therefore, the micropore induced shockwave generating device 25 with themicropore mechanism 251 can obviously reduce the threshold value of the liquid electric effect vacuole generation, greatly reduce the discharge voltage and the discharge current, further realize the generation of strong shock waves under the conditions of low voltage and weak current, obviously improve the system safety and reduce the risk of the system in the using process.
In one embodiment, afluid return tube 30 is disposed within the lumen of theelongate member 21, thefluid return tube 30 being in fluid communication with the workingballoon 22 and theinfusion tube 27, respectively. When the shock wave is generated, the pressure inside the workingcapsule 22 rises, and the arrangement of theliquid return pipe 30 can avoid the risk of balloon breakage caused by overhigh pressure inside the workingcapsule 22. In a preferred embodiment, the distal outlet of the liquid return tube is arranged at the distal end of the workingballoon 22, and the distal outlet of theliquid injection tube 27 is arranged at the proximal end of the workingballoon 22, which can improve the fluid flow efficiency and rapidly relieve the pressure. The micro-hole inducedshock wave generator 25 is a tube body, and twoends 252 thereof are hermetically connected to theliquid return tube 30. In another embodiment, the distal outlet of the liquid return tube is disposed at the proximal end of the working balloon, and the distal outlet of the liquid injection tube is disposed at the distal end of the working balloon. As shown in fig. 5, themicropore mechanism 251 is composed of a plurality ofmicropores 2511 penetrating the wall of the micropore inducedshock wave generator 25. Themicropores 2511 may be arranged orderly or disorderly to form a micropore array, or the micropores may form a honeycomb array. The surface property and the size structure of the micropores meet the requirement of theformula 1, so that the micropores can prevent liquid from passing through and allow gas to pass through. In a preferred embodiment, the microporous means is hydrophobic to further impede passage of liquid through the micropores. The microporous structure can be made hydrophobic by means commonly used in the art, such as coating the surface of the micropores with a hydrophobic coating, or designing the micropores with a hydrophobic structure, or making the microporous structure of a hydrophobic material, or a combination thereof. So that the aim of preventing liquid from passing through the micropores can be fulfilled even if the size of the micropores is in millimeter level as long as the requirement of theformula 1 is met. Therefore, the micropore mechanism can adopt a pore structure with millimeter level, micron level or nanometer level.
In one embodiment, aguide wire lumen 29 is disposed within the lumen of theelongate member 21, a proximal outlet of theguide wire lumen 29 is disposed on thecatheter handle 24, theguide wire lumen 29 extends through the entire lumen of theelongate member 21 and has a distal outlet extending beyond the distal end of theelongate member 21, the proximal end of the workingballoon 22 is fixedly attached to theelongate member 21, and the distal end of the workingballoon 22 is fixedly attached to the distal end of theguide wire lumen 29. Theguide wire lumen 29 is fluidly isolated from the other components of the shockwave balloon catheter 2, preventing liquid from entering the interior of the shockwave balloon catheter 2 through theguide wire lumen 29. Theguidewire lumen 29 is used to receive a guidewire for guiding the catheter to a desired location. When the distal outlet of the return tube is positioned proximal to the working balloon, both ends 252 of the micro-porous induced shockwave generating device 25 may be sealingly attached to the guidewire lumen.
In one embodiment, the elongate member further comprises an outer sheath, the proximal end of the working balloon being in sealing connection with the distal end of the outer sheath, the distal end of the working balloon being in sealing connection with the distal end portion of the guidewire lumen.
In one embodiment, as shown in fig. 6, aprotective balloon 28 is disposed outside the workingballoon 22, a proximal end of theprotective balloon 28 is sealingly connected to theelongate member 21 and surrounds the workingballoon 22, and a distal end of the protective balloon is fixedly connected to a distal end of theguidewire lumen 29. During operation of the system, if the workingcapsule 22 is damaged, the body tissue is not directly exposed to the electric field, thereby avoiding the risk of electric shock.
In one embodiment, the electricfield generating mechanism 23 includes anelectrode pair 231 composed of a positive electrode and a negative electrode, which are electrically connected to thepower module 13 throughwires 26, respectively. The electricfield generating mechanism 23 may include a plurality of electrode pairs 231, which are connected in parallel by a connection wire 261 and electrically connected to thepower module 13 by thewire 26. For example, the electricfield generating mechanism 23 includes two electrode pairs, and the positive and negative electrodes in each electrode pair are respectively connected in parallel through the connecting wires and electrically connected to thepower module 13 through the wires. In a preferred embodiment, the connecting line is of one-piece design with the line. The electrode pair of this application adopts parallel connection effect area big, and the doctor need not operate repeatedly, saves time, and the shock wave is more even moreover, and the effect is better, and is littleer to vascular damage.
Example two
As shown in fig. 7, a micropore induced shockwave balloon catheter system comprises an electric field generating device 1 and the micropore induced shockwave balloon catheter 2, wherein the electric field generating device 1 comprises a man-machine interaction module 11, a control module 12, a power module 13 and a high-voltage pulse output module, the man-machine interaction module 11 is electrically connected with the control module 12, the control module 12 is electrically connected with the power module 13 and the high-voltage pulse output module 14 respectively, the high-voltage pulse output module is electrically connected with the shockwave balloon catheter 2, the micropore induced shockwave balloon catheter 2 comprises an axially extending elongated member 21, a working balloon 22 arranged at the distal end part of the elongated member 21, a catheter handle 24 arranged at the proximal end of the elongated member 21, a lead 26 and a liquid injection tube 27 arranged in the cavity of the elongated member 21, an electric field generating mechanism 23 arranged in the working balloon 22 and a micropore induced shockwave generating device 25 wrapping the electric field generating mechanism 23, the working balloon 22 is in fluid communication with the liquid injection tube 27, the electric field generating mechanism 23 is electrically connected with the high-voltage pulse output module 14 through the micropore induced shockwave generating device, the micropore induced shockwave generating device is capable of preventing the electric field generating device 23 from entering the micropore induced shockwave generating device 251, and the micropore induced shockwave generating device from entering the working balloon 22, and the micropore induced shockwave generating device is capable of isolating the micropore induced shockwave generating device from the working balloon generating device 251. The detailed structure of the micropore inducedshockwave balloon catheter 2 is as described in the first embodiment, and is not described herein again.
The above description is for the purpose of teaching those skilled in the art the present invention and its practical application, and is not intended to limit the scope of the invention, which is to be construed as broadly as possible, and all equivalent variations and modifications which fall within the true spirit and scope of the invention are intended to be embraced therein.